Drying Kinetics and Performance Analysis of Thermal Storage-based Hybrid Greenhouse Dryer for Uniform Drying of Tomato Flakes

This communication focuses on the experimental investigation of mixed heat storage based hybrid greenhouse dryer. The proposed system is a combination of a solar air heater and greenhouse dryer. The mixed heat storage material is applied on the bed of the dryer, which is a combination of paraffin wax and black painted gravel. The tomato flakes were selected for drying in both hybrid system and natural sun drying. Tomato flakes were rehydrated up to 1.29% and 10.10% under hybrid and open modes. The daily drying efficiency for drying tomato flakes in the proposed dryer was 50.18%, while it was 30.02% for open mode. The effective moisture diffusivity was 0.8666 × 1010 m2/s and 11.650 × 1010 m2/s for open and hybrid modes. The embodied energy of the novel hybrid greenhouse dryer was evalauted as 1591.07 kWh, and the cost was calculated as 22664.30, while CO2 emission/year of the system was found to be 33.86 kg. The payback time of the proposed system was found to be 1.87 year; hence the amount invested in the manufacturing of the dryer can be recovered in a shorter period, with higher profit.